Harriet the Spy was banned because it "set a bad example for children." However, not everyone would agree with that assessment. Who would decide what gets said in an advisory?
Books are most commonly banned by school boards (for school libraries) and library boards (for public libraries). These bans usually come after a complaint is received from a single parent.
One book that was banned was Brown Bear, Brown Bear, What do you See? by Bill Martin, Jr. It was banned by the Texas School Board after a board member, Pat Hardy, claimed that Bill Martin had also written a book called Ethical Marxism which she said contained “very strong critiques of capitalism and the American system.”
The problem is that children's author Bill Martin, Jr. and Marxist author Bill Martin were two different people. If Ms. Hardy had done her research--which she should have done before making such a motion--she would have learned that while Bill Martin Jr. had written more than 300 books (including such titles as Chicka Chicka Boom Boom and Polar Bear, Polar Bear What do you Hear?), none of them were on Marxism. In addition, Bill Martin Jr. had not only lived in Texas but the library at Texas A&M University was named after him. In addition, the Bill Martin Jr. Award, which is the Kansas state award for best children's picture book, is named in his honor.
The Texas board very quickly rescinded its decision to ban the book, a ban that never should have happened.